1. Field
The present disclosure relates to a fuel cell system and a method of controlling the fuel cell system.
2. Description of the Related Art
A fuel cell generates power when supplied with hydrogen (fuel gas) and air (oxidant gas) containing oxygen. Such a fuel cell has an optimum power generation temperature (for example, 80 to 90° C. for PEFC) for optimum power generation according to the kind of catalyst (Pt or the like) for electrode reaction of hydrogen or air.
A fuel cell system described in Japanese Unexamined Patent Application Publication No. 2008-135285 includes a sealing valve provided on a cathode off-gas discharge passage for discharging cathode off-gas. The sealing valve seals the cathode off-gas discharge passage during the stop of power generation by a fuel cell.
Accordingly, generation of highly active OH radicals (hydroxyl radicals) is suppressed. As a result, the fuel cell is prevented from being deteriorated by the hydroxyl radicals oxidizing an electrode catalyst layer.